Consider how much thought you put into your Yelp reviews. Dan Jurafsky, a Stanford linguistics professor, and a team of researchers did some deep thinking on nearly 1 million restaurant reviews posted on the San Francisco-based website. And the reviews seemed to say a lot about the psychology of the people who write them.

The study used software to comb over almost 900,000 reviews of 6,548 restaurants in San Francisco, Los Angeles, Boston, Chicago, New York, Philadelphia and Washington, D.C. Researchers used techniques from computational linguistics and what they call “sentiment analysis” to analyze characteristics like the number of words, use of specific pronouns or number of times certain words popped up.

Good reviews of expensive restaurants were rife with metaphors of sex and sensual pleasure, ranging from “orgasmic” pastries to “seductively seared foie gras” (oh my!). There were also lots of drug and addiction metaphors, particularly for pizza, burgers, sweets and sushi (“These cupcakes are like crack”) — and definitely not for vegetables. Women were likelier than men to use such metaphors.

People also busted out their SAT vocabulary for pricey restaurants, using ten-dollar words like “sumptuous,” “commensurate,” “unobtrusively” and “vestibule.”

Negative reviews were straightforward. Popular words included “fail,” “disappoint,” “bad,” “antagonize” and “heartbreakingly.”

What’s more, thumbs-down write-ups also tended to invoke “the language of personal trauma,” as if the reviewers were talking about actual tragedies. Here’s one review, slightly modified by the researchers to disguise the user’s identity:

“The bartender was either new or just absolutely horrible … we waited 10 min before we even got her attention to order … and then we had to wait 45 — FORTY FIVE! — minutes for our entrees … Dessert was another 45 min. wait, followed by us having to stalk the waitress to get the check … she didn’t make eye contact or even break her stride to wait for a response … the chocolate souffle was disappointing … I will not return.”

Such reviews had some characteristics in common with previous studies of victims traumatized by disaster or war, who tend, for instance, to talk about their experience using the pronoun “we” to emphasize a collective sense of grief and solidarity.

“The similarity of one-star reviews to the linguistic characteristics of these trauma narratives suggests a hypothesis that negative restaurant reviews are not simply reviews describing bad food, but rather are trauma narratives, a coping mechanism …for dealing with the minor trauma people experience at the restaurants,” researchers wrote.

“Bad reviews,” Jurafsky explained to Stanford, “seem to be caused by bad customer service rather than just bad food or atmosphere. The bottom line is that it’s all about the personal interactions. When people are rude or mean to you, it goes straight to your sense of self.”

You might think it’s silly to take Yelp reviews so seriously. But Jurafsky makes a compelling defense: “When you write a review on the web you’re providing a window into your own psyche – and the vast amount of text on the web means that researchers have millions of pieces of data about people’s mindsets.”